A system in which a device to device (D2D) communication may be enabled between not just the same cellular providers subscribers but also with subscribers who are from different cellular providers in a region. The system may provide D2D communication interoperability and roaming.

A system in which a device to device (D2D) communication may be enabled between not just the same cellular providers subscribers but also with subscribers who are from different cellular providers in a region. The system may provide D2D communication interoperability and roaming.

A network controller provides proactive notification of a wireless client device's address rotation to layer 2 (L2) and/or layer 3 (L3) devices. Traditional methods of device address discovery rely on broadcasting of address queries across a plurality of links until a path to a device having the queried address responds. As device address changes become more frequent in an effort to improve user privacy, traditional methods of address discovery impose a large burden on networks, reducing their performance and efficiency. By proactively propagating address changes to upstream devices, the need for broadcast oriented address discovery techniques is reduced, resulting in improved network performance.

A network controller provides proactive notification of a wireless client device's address rotation to layer 2 (L2) and/or layer 3 (L3) devices. Traditional methods of device address discovery rely on broadcasting of address queries across a plurality of links until a path to a device having the queried address responds. As device address changes become more frequent in an effort to improve user privacy, traditional methods of address discovery impose a large burden on networks, reducing their performance and efficiency. By proactively propagating address changes to upstream devices, the need for broadcast oriented address discovery techniques is reduced, resulting in improved network performance.

A method for call addition control in a User Agent (UA) or a call service system is provided. The UA or the call service system receives or initiates a call addition request comprising information of a called party during a call. The UA or the call service system determines whether the called party is already present in the call. The UA or the call service system blocks the call addition request in response to the called party being already present in the call.

A method for call addition control in a User Agent (UA) or a call service system is provided. The UA or the call service system receives or initiates a call addition request comprising information of a called party during a call. The UA or the call service system determines whether the called party is already present in the call. The UA or the call service system blocks the call addition request in response to the called party being already present in the call.

An operation method of a first terminal may include: configuring a Uu access link with a base station, and receiving a first message from the base station, the first message including a relay RNTI for identifying the first terminal, a node address of the base station, and a RAP entity ID for identifying a RAP entity configured for the first terminal; configuring a relay link with a second terminal when communication with the base station is disconnected; requesting link switching by transmitting to the base station a second message via the second terminal, the second message including the relay RNTI, node address, and RAP entity ID; and receiving a response to the second message from the base station via the second terminal, and switching a link with the base station from the Uu access link to the relay link.

An operation method of a first terminal may include: configuring a Uu access link with a base station, and receiving a first message from the base station, the first message including a relay RNTI for identifying the first terminal, a node address of the base station, and a RAP entity ID for identifying a RAP entity configured for the first terminal; configuring a relay link with a second terminal when communication with the base station is disconnected; requesting link switching by transmitting to the base station a second message via the second terminal, the second message including the relay RNTI, node address, and RAP entity ID; and receiving a response to the second message from the base station via the second terminal, and switching a link with the base station from the Uu access link to the relay link.

A method for conducting a velocity check for outbound subscribers roaming to neighboring countries includes receiving, by a network gateway associated with a home country from an MSC associated with a neighboring country, an ingress signaling message related to a mobile device roaming in the neighboring country, sending, to an HLR in the home country, an interrogation request message containing a mobile subscriber identifier, and receiving an interrogation response message containing age of location information and cell identifier information corresponding to the mobile subscriber identifier. The method further includes utilizing the cell identifier information and a country code identifier included in the ingress signaling message to determine two latitude-longitude positions, determining an estimated transit time of the mobile device using the two latitude-longitude reference positions, and comparing age of location information with the estimated transit time to determine if the ingress signaling message is to be forwarded to the HLR.

A method for conducting a velocity check for outbound subscribers roaming to neighboring countries includes receiving, by a network gateway associated with a home country from an MSC associated with a neighboring country, an ingress signaling message related to a mobile device roaming in the neighboring country, sending, to an HLR in the home country, an interrogation request message containing a mobile subscriber identifier, and receiving an interrogation response message containing age of location information and cell identifier information corresponding to the mobile subscriber identifier. The method further includes utilizing the cell identifier information and a country code identifier included in the ingress signaling message to determine two latitude-longitude positions, determining an estimated transit time of the mobile device using the two latitude-longitude reference positions, and comparing age of location information with the estimated transit time to determine if the ingress signaling message is to be forwarded to the HLR.